I agree with all the statements said against Loki. He sucked horribly in this movie, but I thought it was great. I'm looking forward to seeing some of the Xmen or maybe Spiderman in Avengers 2.
The Hulk was actually my favorite in the film other then of course RDJ as I knew he would be a scene stealer. And yet, I felt all the Avengers got equally represented in this film.
As a super hero action film it stood it's ground. Over-intellectualizing this sort of genre is pointless, but for some reason people still do it.